Quartz lamp base and socket



NOV. 25, 1969 B, R, FALLON QUARTZ LAMP BASE AND SOCKET Filed April 25,1967 mami INVENTOR Bernard R. Folon WITNESSES M JW ATTORN EY UnitedStates Patent O 3,480,816 QUARTZ LAMP BASE AND SOCKET Bernard R. Fallon,Clark, NJ., assignor to Westinghouse Electric Corporation, Pittsburgh,Pa., a corporation of Pennsylvania Filed Apr. 25, 1967, Ser. No. 633,531Int. Cl. H013 /48, 5/50 U.S. Cl. 313-51 3 Claims ABSTRACT OF THEDISCLOSURE A novel lamp base and socket is particularly adaptable toprojection lamps because accurate orientation of the lamp filament iseffected. A large, positive area for electrical contact is provided byflat recessed base conductors. Socket spring conductors effectelectrical contact and also act in conjunction with recessed basesurfaces to retain the base in position.

Background of the invention This invention relates to an electric lampbase and socket combination particularly adaptable to projection lamps.

The projection lamp art exacts critical demands for orientation of thelamp filament to insure proper focusing and display. The lamp base andsocket combinations presently used for such lamps include simplethreaded base and socket assemblies which present serious orientationproblems. Also used are assemblies utilizing pin type contact elementswhich are clumsy to insert and are easily bent and damaged when usedwith these relatively small lamps. These lamps have a relatively highpower input and means for providing sufficient electrical contact areafrom the base to the socket conductors is very important. The basespresently used also restrict natural ventilation of the press portion ofthe lamp envelope, which can result in overheating and shortenedoperational lifetime of the lamp.

Summary It is an object of this invention to provide a novel lamp baseand socket which in combination positively orient the lamp filament of aprojection lamp and retain the lamp in a fixed predetermined position.

It is another object to provide such a lamp base and socket with flatconductive contact members for ease of lamp mounting and which contactsprovide a larger and more positive area of contact.

It is still another object to provide a simplified base and socketdesign thereby simplifying the lamp manufacturing process by minimizingtolerance problems yet retaining positive filament orientation.

It is a further object to provide a lamp base and socket allowingnatural ventilation of the press area of the lamp.

These objects and other that will become apparent as the descriptionproceeds are accomplished by providing a novel base and socket. The baseis an insulating hightemperature-stable member provided with a centrallydisposed slot in which the press portion of the lamp is affixed.Electrically conductive base elements that are connected to the lamplead wires are disposed as exterior recessed surfaces. The socket is aninsulating high-temperature-stable member substantially conforming inshape and diversion to the base to accept the base. Also, electricallyconductive socket spring contact means are provided to contact the flatrecessed base contacts and thereby mechanically retain the base in astable, predetermined, oriented position.

Brief description of the drawings For a better understanding of theinvention and its capabilities, reference is made to the followingdrawings, wherein:

icel

FIGURE 1 is an elevation in cross-section of the base and a fragmentaryportion of the lamp;

FIG. 2 is an elevation in cross-section of the socket; and

FIG. 3 is a plan View of the socket before the socket contact membershave been affixed.

Description of the preferred embodiments With specific reference to thedrawings the lamp 10 comprises a sealed vitreous light-transmittingenvelope 12 having a flattened press portion 14. An incandesciblefilament 16 is provided within the envelope 12 and is supported in apredetermined oriented position with respect to the press 14 by supportmeans 17 which here consists of the internal conductors but can be anindependent support means within the lamp. The envelope 12 encloses apredetermined pressure of preselected fill gas, such as argon and apredetermined amount of additive material such as iodine. Lead-inconductors 18 are sealed through the press and electrically connect tothe lamp filament 16.

The lamp base 20 comprises an electrically insulatinghigh-temperature-stable member 22 having a generally rectangularcross-section. The insulating member 22 is provided with a deep,centrally disposed slot 24 having opposite elongated sides generallyparalleling opposite external sides of the insulating member 22.. Theslot 24 is so disposed as to open into at least one predeterminedsurface 26 which faces the lamp filament 1-6. This insulating member 22is formed of a thermosetting resin such as phenolic epoxy, or is formedof ceramic or similar insulating material. The lamp press portion 14 ispositioned within the slot 24 with the flattened sides of the press 14generally paralleling the elongated sides of the centrally disposed slot24. A high-temperature-stable electrically insulating cement 28substantially fills the portion of the centrally disposed slot 24 whichis not occupied by the press 14 and the cement 28 afixes the press 14 tothe insulating member 22. This cement 2S is a high temperature resistantmaterial, for example a material with a sodium silico fluoride settingagent and Zircon filler, or other ceramic type cements as are known inthe art. Two of the opposite exterior surfaces 30 of the insulatingmember 22 which generally parallel the elongated sides of the slot 24are provided with a recessed surface portion 32 contiguous to thepredetermined surface 26 which faces the lamp filament 16. The recessedsurface portion 32 generally parallels the elongated sides of thecentrally disposed slot 24. The recessed surface portions 32 extendsaway from the insulating member surface that faces the filament and mayterminate at a ledge 33 provided between the recessed surface portion 32and the exterior surface 30 of the insulating member 22. This ledge 33acts in conjunction with the socket spring contact means 54 afterinsertion to mechanically retain the base 20 in the predeterminedposition.

The base 20 is provided with two flattened U-shaped electricallyconductive base contact members 34. One leg 36 of the base contact 34projects away from the lamp filament 16 and is fitted into the recessedsurface portion 32. The other leg 38 of the base Contact 34 projectsaway from the lamp filament 16 and is affixed between the press 14 'andthe sides of said slot 24 and is retained in position by the cement 28.The base contacts 34 are electrically connected to the lamp lead-inconductors 18. The base contacts are made of a material such as brass.

At least one of the electrical connections between the base contacts 34and the lamp lead-ins 18 may include a fuse 19 which may be fuse-wiredisposed within the slot and retained in position by the cement 28.

The improved socket 40 comprises an electrically insulatinghigh-temperature-stable socket member 42 which is provided with agenerally rectangular centrally disposed cavity 44. The cavity 44 opensinto one predetermined socket surface 46 and substantially conforms inshape and dimensions to the base member 22 allowing insertion of thebase into the socket cavity 44. The insulating socket member 42 is madeof a thermosetting resin such as phenolic epoxy, or is formed of ceramicor similar material.

The socket 40 has two electrically conductive socket contact members 48which are mechanically attached to and extend through the elongatedopposite sides of said socket member 50-52. A portion of each of thesocket contacts 48 extends a predetermined distance into the cavity 44as an inwardly disposed spring contact means 54. The spring contact 54is compressed outwardly by the base member 22 upon initial insertion ofthe base member 22 into the socket cavity 44. The spring contacts 54electrically contact the base contacts 34 upon further insertion of thebase 20 into the socket cavity 44. The spring action of the springcontact means 54 exerts a positive holding action against the basecontacts 34 both to insure electrical contact and to mechanically retainthe base 20, when the recessed surface portion 32 of the exteriorsurface of the base member 22 is encountered upon further insertion ofthe base member 22 into the cavity 44. The socket contact members 48 areadapted to be connected to a source of electrical energy for poweringthe lamp 10. The socket member 42 is adapted to be mechanically mountedin a predetermined position.

The socket has Ventilating slots 56 provided in opposite sides of thesocket member 42 and opening into the centrally disposed cavity 44. TheVentilating slots 56 allow for natural ventilation of the press portion14 of the lamp 10.

It will be recognized that a novel lamp base and socket combination hasbeen provided that positively orients the lamp lament. The base has flatrecessed electrical contact members to provide a large positive area ofelectrical contact in conjunction with socket spring contacts. Thespring contacts act to mechanically retain the base securely inposition, and the recessed contact position insures retention of thebase in position.

It is to be understood that while a specific detailed description of theinvention has been given, the invention is not to be limited thereto orthereby.

I claim as my invention:

1. In combination with an incandescent lamp comprising a sealed vitreouslight-transmitting envelope having a attened press portion, anincandescible lament within said envelope, said filament supported in apredetermined oriented position with respect to said press, saidenvelope enclosing a predetermined pressure of preselected ll gas, andlead-in conductors sealed through said press and electrically connectedto the said lamp filament, the improved lamp base comprising:

(a) an electrically insulating high-temperature-stable member having agenerally rectangular cross-section and provided with a deep centrallydisposed slot having opposite elongated sides generally parallelingopposite sides of said insulating member, said slot opening into atleast one predetermined surface of said insulating member, and one ofsaid predetermined surfaces of said insulating member facing said lampfilament, said envelope press portion positioned within said slot withthe attened sides of said press portion generally paralleling saidelongated sides of said centrally disposed slot;

(b) a high-temperature-stable electrically insulating cementsubstantially lling the portion of said centrally disposed slot which isnot occupied by said press portion and afiixing said press portion tosaid insulating members;

(c) the two opposite exterior surfaces of said insulating member whichgenerally parallel said elongated sides of said slot each being providedwith a recessed surface portion contiguous to and extending away fromsaid predetermined surface which faces said filament, and each saidrecessed surface portion generally paralleling said elongated sides ofsaid centrally disposed slot, said recessed surface portion terminatesat a ledge provided between said opposite exterior surfaces and saidrecessed surface portion; and

(d) two flattening U-shaped electrically conductive base contact memberseach having one leg thereof projecting away from said filament and ttedinto said recessed surface portion and said ledge, the other leg of saidbase contact members projecting away from said filament and affixedbetween said press and the sides of said slot and retained in positionby said cement, and said base contacts being electrically connected toeach of said lamp lead-ins.

2. The base as specified in claim 1, wherein at least one of theelectrical connections between said base contacts and said lamp lead-insincludes a fuse.

3. ln combination with an incandescent lamp comprising a sealed vitreouslight-transmitting envelope having a flattened press portion, anincandescible filament within said envelope, said filament supported ina predetermined orientated position with respect to said press, saidenvelope enclosing a predetermined pressure of preselected ll gas, andlead-in conductors sealed through said press and electrically connectedto the said lamp lament, the improved lamp base and socket combinationwhich comprises:

(a) said improved base comprising:

(1) an electrically insulating high-temperaturestable member having agenerally rectangular cross-section and provided with a deep centrallydisposed slot having opposite elongated sides generally parallelingopposite sides of said insulating member, said slot opening into atleast one predetermined surface of said insulating member, and one ofsaid predetermined surfaces of said insulating member facing said lampfilament, said envelope press portion positioned within Said slot withthe flattened sides of said press portion generally paralleling saidelongated sides of said centrally disposed slot,

(2) a high-temperature-stable electrically insulating cementsubstantially filling the portion of said centrally disposed slot whichis not occupied by said press portion and afxing said press portion tosaid insulating member,

(3) the two opposite exterior surfaces of said insulating member whichgenerally parallel said elongated sides of said slot each being providedwith a recessed surface portion contiguous to and extending away fromsaid predetermined surface which faces said filament, and each saidrecessed surface portion generally paralleling said elongated sides ofsaid centrally disposed slot, said recessed surface portion terminatesat a ledge provided between said opposite exterior Surfaces and saidrecessed surface portion; and

(4) two flattened U-shaped electrically conductive base contact memberseach having one leg thereof projecting away from said filament and ttedinto said recessed surface portion and said ledge, the other leg of saidbase contact members projecting away from said filament and affixedbetween said press and the sides of said slot and retained in positionby said cement, and said =base contacts being electrically connected toeach of said lamp lead-ins;

(b) said improved socket comprising:

(l) an electrically insulating high-temperaturestable socket memberprovided with a generally rectangular centrally disposed cavity openinginto one predetermined surface thereof and substantially conforming inshape and dimension to said base to allow insertion of said base intosaid cavity,

(2) two electrically conductive socket contract members mechanicallyattached to and extending through the elongated opposite sides of saidsocket member, a portion of each said contact extending a predetermineddistance into said cavity as an inwardly disposed spring contact tainsaid base in predetermined position, and said socket contact membersadapted to be connected to a source of electrical energy for poweringthe lamp; and

(3) said socket member adapted to be mechanically mounted in apredetermined position.

means, said spring contact means being compressed outwardly by said baseupon initial insertion of said base into said socket cavity, uponfurther insertion of said base into said socket 10 References CitedUNITED STATES PATENTS cavity, said spring contact means electricallySroveniller contacting said base contacts, and the spring 3274426 9/1966soelscd 13T' 8 action of said spring contact means as well as co e ge 351 X the contact of said spring Contact means with the portion of saidbase contact member which JAMES W' LAWRENCE Pnmary Examiner its saidledge portion of said base member E. R. LAROCHE, Assistant Examinerexerting a positive holding action against said base contacts both toinsure a broad surface U-S- Cl- X-R area of electrical Contact and tomechanically re- 339-145, 25 6

